Current research has indicated that microwave radiation acts synergistically with low pH to cause tumor remission. Athough hyperthermia has been shown to effectively eradicate and cause regression of soft tissue sarcomas, melanomas, and other surface tumors, there have been no clinical studies with eye tumors. This project will determine the safety and efficiency of combining heat and hyperacidification as a means of treating intraocular cancer. Using microsurgical techniques, Greene melamona will be implanted subchoroidally into the eye of albino white rabbits using the opposite untreated eye as a control. One-half of the treated rabbit eyes will be clinically altered with hyperglucidification to produce high viscosity and a low pH. Hyperthermia will be delivered with a 200-mW microwave generator with shielded wave-guide cable and a dipole antennae and reflectors to the eye of the anesthetised rabbit. Effects of the heat and acidification on the cornea, retina, and tumor will be carefully studied and mapping of intraocular temperatures will be accomplished. This model will provide a unique and direct means of visualizing tumor destruction using microwave radiation and may lead to a new, relatively non-invasive method for treating cancer of the eye. Equipment used in this project will be adaptable for future clinical studies and application.